Governing system



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a sneqxs-sneet 1 A FLAT V/VE fea l/aza- J. J. RING ET'AL GOVERNINGSYSTEM Filed Feb. 8, 1940 fas (20S/AIG 4 A 67 /5 M9422 zo /2 oct. 12,1943.

2 Sheets-Sheet 2 J. J. RING ET AL GOVERNING SYSTEM Filed Feb. 8, 1.940

Oct. 12, `1943.

mum@ s/o 2 Z t M 4 o mz @W 7 9 4 8 5u 8 o WH n@ w 2 O l f 5 5. o n Lm. 62 4 ww n a 3 w Z y 7 o 22 M. 6 2 2 a 6 Mw D. o/ Mx 3 O OM 7 PatentedOct. 12, 1943 I GOVERNN G SYSTEM Joseph J. Ring, Wauwatosa, and BeverlyR.

Nichols, Elm Grove, Wis., assignors to Allis- Chalmers ManufacturingCompany, Milwauhee, Wis., a corporation of Delaware Appication' February8, 1940, Serial N o. 317,809l

(ci. rar-15s) 9 Claims.

This invention relates generally to improvements in governing systemsfor uid pressure operated prime movers and more particularly to systemsfor governing hydraulic turbines of the adjustable runner vane type.

Governing systems for hydraulic turbines of the adjustable runner vanetype must provide accurate and quick response to both normal andabnormal operation of the turbine and must also provide for Anormalmaintenance of predetermined relations between the gate controlling theflow of pressure iluid and the positioning of the runner vanes withprovision for variation of such relations when desired. When a verysensitive speed responsive element is employed in such 'governingsystems, such element does not become initially effective until theprime mover has come to nearly the desired operating speed and the speedresponsive means may, at that time, not be sufficiently quicklyl'eSlJOnsive to speed variations to preventoverspeeding of the unit.Thus it is desirable to provide governing systems with means forpreventing overspeeding of the unit during starting of the unit and ofthe governing system. A governing system must also be adjustable'topermit only a predetermined variation from the desired speed,particularly when a plurality of prime movers are operated in parallel,to permit each of the several units to take on more load when requiredWithout causingsuch rapid alternate taking on and rejection of load aswill aiect the stability of operation of the prime mover. Due to thefact that some machines have a greater overload capacity than others, itis, however, necessary to provide means for preventing any one machinefrom taking on an excessive overload While other parallel operatingmachines are running comparatively underloaded.

When some abnormal condition occurs inthe operation of a prime mover,means must be provided which will shut oli the flow of fluid to themachine either partially or completelyrdepending on the character of theabnormal condition than'existing. If such abnormal condition is onlytemporary and not dangerous to the machine, the machine should be shutdownonly to no load synchronous speed, but if the condition is likely toexist for an appreciable time and to become progressively worse until.relatively dangerous to the machine, it is necessary to shut oil. theflow of operating uid completely in such manner that the machine cannotbe restarted until aiter the abnormall condition has been corrected.Means should also be provided interlocking the normal adjusting means ofthe governing system with the abnormal conditionl responsive means,particularly when the normal adjusting means are remotely operated, topre-` vent any effort on the part of the machine operator to continueoperation of the machine in l spite of the continuance of abnormalconditions.

lIn governing hydraulicfturbines of the'ad instable runner Vane type, aVixed relation must be maintained between the degree of gate open` ingand the setting of` the runner vanes which determines the area of'waterpassages between the' runner vanesi lThe runner vane adjusting meansmust therefore be accurately and rapidly responsive to'changes in' theposition ofthe gate without any appreciable la'g 'or any tendency tooverrunthe vane setting required by the then existing gateposition;During'`v starting offthe turbine, the then normally relatively flatposition of 'therunner vanes is, however, not desir-- able Vbecause whenthe vanes are in such flat position, itis possible .to obtain onlyavery'low torque ata high speed, Whereas the starting requirements are avery high torque at "a '10W Vspeed which demands a relatively steep tiltof the runner vanes. The `runner vane adjusting means `mustthereforebeprovided'with means by whichV its'normal operation can be.neutralized and .by lwhich the requirement for steep tilting of thevanes during thestarting operations 'of the governing'syst'em maybe met.r Under some conditions of operation of the governing system or of thehydraulic turbine itselfgit may be neces-k sary to operate the turbineas a ixed runner machine or to conserve the fluid pressure used as thepower for operating the governing system. The rst above condition is metby providing means for locking the runner vane .adjusting means'in afixed position responsive to manual operation, or automaticallyresponsive to predetermined conditions, and the second above con'-dition'is met by manual or uid responsive means for interrupting theflow of iuid pressure tothe servomotor for positioning the runner'vanes.

Whena governing system` is providedv with many automatic lmeans'iorperforming various functions as above indicated, such automatic meansmay require adjustment or yreplacement at `times When the primemovermust be kept in operation for other reasons. It is therefore de sirableto provide means which will cut out or bypass all of the automaticcontrols excepting the restoring means for returningA the controlvalvevto mid-position when suchfvalve controls the flovv of pressure toa'gatecperating servomotor and the maximum load limit means associatedwith such restoring means. The present invention therefore providesmanually operable means for controlling the operation of the turbinewithout the use of the various automatic means included in the governingsystem.

It is therefore an object of the present invention to provide agoverning system for prime movers in which both normal and abnormalconditions of operation of the prime mover are effective to vary thecontrol of the prime mover by the governing system.

Another object of the invention is to provide a prime mover governingsystem which includes means for adjustment of the normal startingconditions and for maintaining normal operating speed and load capacityof the prime mover.

Another object of the invention is to provide a prime mover governingsystem which provides for either partial or complete shut down of themachine dependent on either of several abnormal conditions then existingand in which further adjustment of the governing system is impossibleduring the existence of such abnormal condi- Another object of theinvention is to provide a prime mover governing system with manuallyoperable means eliminating the action of automatic portions of thesystem when operation of the prime mover is required regardless of theaction of such automatic means.

Objects and, advantages other than those set forth above, will beapparent from the following ydescription when read in connection withthe accompanying drawings, in which:

Fig. 1 diagrammatically illustrates a hydraulic turbine driven electricgenerating unit having applied thereto an automatic speed and loadgoverning system embodying the various elements and subcombinations ofthe present invention;

Fig. 2 diagrammatically illustrates the application of remotelycontrollable means to the synchronizing screw and the load limit screwshown in Fig. 1.

`The various elements constituting the present control or governingsystem are not shown in their relative positions, their true size nor intheir relative proportions, but are shown entirely diagrammatically tofacilitate explanation of the construction and operation of the system.

Referring to the drawings by characters of reference, the governingsystem is shown as applied to a prime mover such as a. hydraulic turbinegenerally indicated at 6 and shown as being of the adjustable vanepropeller type driving a conventional electric current generator 1. Theturbine 6 has the usual casing 8 forming a peripheral water inlet inwhich are mounted a plurality of movable vanes 9 forming a gatecontrolling the flow of fluid into the turbine. The term gate isintended to include any means used for the purpose of controlling theflow of fluid pressure to any prime mover to which the governing systemof the present invention is applicable. Gate vanes 9 are connected byconventional linkage to a shifting ring II mounted on the turbine casingfor movement into different positions to control the position of thegate varies and hence to control flow of water into the turbine. Theshifting ring II is connected with and actuated by a piston I2 movablewithin a cylinder I3, the piston I2 and cylinder I3 forming a nuidpressure operated servomotor controlled by an automatic pilot valve I4in the governing system of the present invention.

The turbine 6 is connected with the generatoi` 'l by a hollow shaft I5which, at its end within the turbine casing 3, is provided with a hub IBin which are journaled a plurality of propeller vanes Il extendingsubstantially radially from the hub. The several propeller or runnervanes Il are interconnected internallyof the hub I6 by any one ofseveral known means, to an operating rod I8 which extends upwardlythrough the shaft I5 to connect with a piston I9 movable within cylinder20 which is either inserted in or formed as a portion of the shaft I5.It will be understood that the relative positions of the runner vanesgovern the area of the fluid flow passages or openings between the vanesand that adjustment of the runner varies to increase or decrease sucharea depends on the direction of movement of the vanes. The runner vaneoperating servomotor I9, 2li, is double acting and is operated by fluidpressure admissible to the upper side of the piston I9 through apassageway 22 formed in the shaft I5 and by uid pressure admissible tothe lower side of the piston I9 through a tube 23 extending through thepassage 22 in the shaft I5 and communicating with the underside ofthepiston I9 by way of passage 2i through such piston. The tube 23 is xedlymounted on the piston I9 and accordingly moves with such piston. Fluidpressure is transmitted either through the passageway 22 or the tube 23by way of a so-called distributing head having two chambers 26 and 2l'connected with the passageway 22 and with the tube 23 respectively. Flowof iiuid pressure to the distributing head-chambers from a suitablesource (not shown) is controlled by -a pilot valve 28, thestem 29 of thepilot valve 28 being shiftable automatically to maintain a predeterminedrelation between the positions of the gate vanes 9 and the runner vanesI1.

Fluid pressure is applied from a suitable source (not shown) to theautomatic pilot valve I4 by way of a pipe SI and a pipe 32 and. undercontrol of the pilot valve, is supplied to the gate operating servomotorI2, I3 through pipes 33 and 34. Pressure is discharged from theservomotor I2, I3 by way of the pilot valve I4 into a pipe 35 leadingback to the source of fluid pressure. The stem 35 of the automatic pilotvalve I4 is connected with one end of a lever 38 having as its fulcrum axedly mounted screw 39 operable locally by means of the hand wheel I orremotely by suitable means. The other end of the lever 38 is connectedby way of the linky 42 with a iioating lever 43 of which the fulcrurn isformed by the piston of a fluid pressure operated servomotor Il suppliedwith pressure through the pipe 4t and discharging through the pipe 4l.The supply of fluid through the pipe 46 to the servomotor 44 iscontrolled by a valve (not shown) which is operated by a fiyballstructure 48 driven by a motor 49 responsive to the speed of thegenerator 1. The detailed structure of the servomotor 154, theservomotor control valve, the iiyball head 4S and the motor 49 can beseen in Patent No. 2,106,- 684, issued January 25, 1938 to J. J. Ring,B. R. Nichols and A. Pfau, and such structure is acco-rdingly not shownherein in detail, and will be described only sufciently to allowcomprehension of its functional cooperation with other portions of thepresent control system. Variations in load on and hence speed of thegenerator 'I which produce variations in speed of the motor i9 andlyball structure 43, causes movements of the servomotor 44 and theleverage 43, e2 and 38 to actuate the gate pilot valve I4 `which movesto admit pressure for operating the gate servomotor I2,v I3 and hence toshift the gate 5 in either direction dependent on the sense of the speedchange. y

Every movement of thel gate servoinotor pi.,- ton I2 must be relayed tothe flyball iioating lever 43 and hence to the `sate pilot valve I4 torestore such valve to neutral position after each `movement thereof tothereby prevent movement of the. gate 9 beyond a desired position. Suchrelay comprises a cable l'attached? at oneend to the gateservomotorfpiston l2 and passing respectively over pulleysA 52, 53, `511and 55 with the free end of the cable attached to a weight 57 to keepthe cable taut. The cable 5i permits location of the servomotory I2, i3pvvherever desired and at a Adistance from the remainder of thegoverning system. To secure stable operation of the turbine and to allowonly a predetermined speed difference betweenno loadand full loadgatevane opening to thereby meet requirements from maintenance of thespeed and hence of constant frequency of the generator, pulley 54 isconnected through a dashpot andV linkage with the flyball yiioatinglever t3, The dasbpot comprises ay casing 58 divided into tivo chambersby a partition and by pistons is and SG and pro* vided with a valve @lfor controlling the rate of flow of fluid under pressure from onedashpot chamber to the other. Pulley 5a is fixedy mounted on a shaft 52supported on a fixed bracket 63 and the pulley shaft has fixed thereonan arm 6ft connectedwith the vpiston 59. The dashpot piston Sil isconnected by a lever fili and a link 5'! with one end of the flyball'floating lever 13. It will be understood that all movements of the gatevane servomotor 52, i3 are relayed to the fioating lever t3 through thedashpot and linkage iid, E5. El thus providing means for returning thegate pilot lvalve hito the neutral or mid position 'after each movementthereof and that such returning actions are subject to the dampingaction of the dashpot. Y

Although there must be some speed difference between no load and full`load gate vane position to'insure stability of operation of the primemover `generating unit, such difference shouldbe kept as small aspossible tosecure the maximum sensitivity of the governing system tospeed changes. Provision must therefore be made to adjust the pilotvalve return or restoring means to regulate the speed difference ordroop permitted between the two load limits stated. Such means includear link 'll connected with the lever S3 and with an arm 'I2 pinned on ashaft 'Va mounted on the bracket'ES. .Another arm i4 is .alsopinned onthe shaft 'J3 and is provided with a slot in which is engaged a pinextending vfrom an arm lf mounted on anut 'Il traveling on a screw 'l5which is 'rotatable by a hand wheel la, the arm l5 and its adjusting nut'I and screw 'i3 being mounted on and rotatable with the shaft EE.Movement of the nut TI will increase or decrease the effective length ofthe arm .it thus permitting adjustment of the fulcruiml point of lever6d and hence of the'speed difference or droop be tween no load andvfullload gate vane position to any degree predetermined by load conditions.The percentage of speed droop permitted is increased by lengthening thearm 'le and vice versa,l the lengthening being obtained byk moving thenut l1 away from the shaft E2. I l

It is desirableto provide a prime mover governng system with meansforlimiting'the maximum power output thereof or the load which may beapplied to .the prime mover. Such means are included in the presentsystem `and vinclude a collar 8l mounted on the stem 3B ofthe automaticgate pilot valve |14 which collar 8l is engageable `with a finger 82keyed on a shaft 83.

An arm 84 is keyed on the shaft 83 and is con-k power of the unit islimitedy by thesetting of the load limit device. As shown in Fig. 1,vthe vload limit device is set in a .5 gate position, that is the Din ofcrank `8'1 is centrally located in the slot of rod 92 to prevent openingof gate 9 beyond the .5 position. `I f thefvalve Ill is moved in gateopening direction, gate servcmotor move ment in the opening directionrotates pulley 54 counterclockwise which moves rod 82 toward the left.If the gate opening movement tends to so beyond the .5 gate position,movement of rod S2 causes the pin .of crank S1 to engage the right handend of the slot in roi-192 which rocks crank 8'! counterclockwise andmoves n'ger 32 clockwise to engage withvcollar 3l .and pushes valve i4to mid-position thereby preventing movement of thel gate beyond the .5opening set. It will be apparent that the adjusting nut 38 varies theposition of the pin ,of crank 81 within the slot of rod 92 and thuspermits adjustment of the maximum power output of the prime mover unit.The load or power limitingdevicemay v be used either for manuallysecuring any desired opening of the gate vanes orfor limiting themaximum opening of suchgate as has justbeen described. v

Under some conditions .ofoperation of 4the primemover generating unit,it may' become necessary to close the gate partially to no loadsynchronous speed positionor even to completely interrupt operations ofthe unit.' A. portion 96 of the governor base supports a cylinder 9i'containing a piston I98 biased toward one end of the cylinder by acompression spring 99. vFluid pressure may be supplied 'to the cylinder97 from a suitable source under the control of a valve llthrough a pipem2.- Pressure is discharged from the cylinder 91 under the controlof avalve las. Valves lill and |03 are connected by a lever 'IM which isoperable by a normally deenergized solenoid HB6; against springs actingon each valve. `A latch lill which is actuated by a normally deenergizedsolenoid |68 prevents further operation of solenoid` IGS and valves lillVand ID3 until after such latch has been reset following each operationthereof, The solenoids it l and S are connected for energizationresponsive v'into the slotted portion of the piston rod for ensagementtherebwwben `the oilfpressure in the cylinder 91 is released. The otherarm of bell crank ||I extends adjacent a linkage between the shaft 83and a shaft ||2, the linkage comprising an arm |I3 keyed on shaft B3 andan arm ||4 keyed on shaft |I2, the two arms being joined by links I I5and I IS.

Threaded extension |09 of the piston rod is located to engage one arm ofa bell crank ||1 mounted on the base portion 96, the other arm of thecrank being connected with an adjustable rod I I8 ending in a roller II9 resting on the base 0S and movable againsty a stop |20 formed by thebase. A spring |2| tends to rotate crank ||1 in counterclockwisedirection to a suflicient extent to allow the roller I I9 to drop backof a latch surface |22 formed on the base portion 90 where the roller isnormally retained. A normally deenergized solenoid |25 is connected forenergization responsive to any desired condition of the unit which maybe employed to close and open an electric circuit and has its coreconnected by links |21 and |28 with a shaft |29 suitably mounted on thegovernor base 9S. The shaft |29 also has secured thereon a bell crank|3| to one end of which is pivotally connected a push rod |32 having anenlarged head and being guided in its movement in an aperture formed inthe governor base 96. The other arms of the crank ISI extend to adjacentthe base 9S and can rest against the base as a stop When solenoid |26 isdeenergized to permit rotation of the crank |3| in a counterclockwisedirection.

When a predetermined emergency arises, which requires only partial shutdown of the unit to no load synchronous speed, solenoid |08 is energizedto retract latch |01 and solenoid |06 is energized to close valve |0|and open valve |03. Spring 99 then expands to force fluid from underpiston 98 and the piston descends until extension |09 engages bell crankIII and rotates the bell crank counterclockwise to engage link IIS androtate arm H3, shaft 83 and iinger 82 in clockwise direction whichpresses nger 82 on load limit collar 8| and causes pressure admissionthrough pilot valve I4 to the right hand end of gate servomotor I2, I3to move the gate 9 in closing direction until the unit has come to noload synchronous speed. During the above action nuts I I0 have beenbrought into Contact with one arm of bell crank III and further downwardmovement of piston 98 is arrested.

If the emergency is of such nature as to require complete shut down ofthe unit, solenoid |36 is energized. Upon such energization, the core ofthe solenoid |26 is raised and rotates shaft |29 which swings crank I3Iclockwise and forces rod |32 upward to raise roller ||9 from the surface|22. Pressure due to the spring 99 tends to rotate the crank ||1clockwise and pulls the roller I|9 against stop |20, thus allowing crank||1 to rotate and permitting spring 99 to expand fully and move thepiston 98 to the extreme end of the cylinder 91. To place the Vsystemagain in condition for normal starting, solenoid |08 must be energizedto remove latch |01 from under link |04 and allow it to return to itsnormal position and the condition which caused energization of solenoids|06 and |20 must be removed.

When the prime mover generating unit is being started from standstill,it is necessary to prevent opening of the gate beyond the amountrequired to bring the unit up to synchronous speed at no-load untiltheilyballs have reached substantially synchronous speed and lare thereforein position to assume control of the governing system and hence of theunit. A bracket |36 is mounted on the piston rod of the flyballservomotor 44. A bell crank |31 is mounted on a fixed portion of thegovernor base adjacent the bracket I 30 and one arm thereof carries alink |38 passing through the bracket, the link being screw threaded andhaving nuts below the bracket to limit the motion, in one direction, ofthe link relative to the bracket. The other arm of the crank |31 isconnected by a rod |39 with a latch member I 40 freely pivoted on an arm|4I keyed to the shaft 83. The latch member |40 and the arm |4I aredrawn toward each other by a spring |42. The latch member |40 is adaptedto Contact with a latch member |43 which is rotatably mounted on theshaft |I2 and is biased in counterclockwise direction by a spring |44.The latch member |43 has pivoted thereto a link |46 passing through anaperture in one arm of a bell crank |41 keyed on the shaft ||2, theother arm of the crank |41 beine pivotally connected with the lever 92which is connected With the load limit crank 81 and with the shaft 62 ofthe rst restoring or relay means.

When the turbine is being started from a normal shut-down position, oilis present in the cylinder 91 which has raised the piston 98 and allowedcrank to move out of contact with link IIS thus freeing the shaft 83from restraint on its rotation. The Wheel 4| is then rotated to raisefloating lever 33. Pilot valve I4 is then raised to operate the gateservomotor I2, I3 in gate opening direction which rotates pulley 54 in acounterclockwise direction and shifts the rod 92 and the crank I 41attached thereto toward the left. The spring |44 may then pull the latch|43 in a counterclockwise direction to engage with the latch |40.Continued movement of the restoring mechanism continues counterclockwisemovement of pulley 54 and pulls rod 92 further toward the left whichrocks crank |41 further in a clockwise direction. Spring |44 pulls latch|43 against latch |40 and rotates latch I 40 about its connection withrod |39 as a pivot. Such pivot is movable because rod |39 can swingabout its connection with the crank 31. The upper end of latch |40 actson the end of arm I4I to rotate the shaft 83 and to rock the nger 82toward the collar 8| to prevent opening of the gate 9 beyond apredetermined amount. As the flyballs 4S come up to speed and raisebracket |30 off the nuts on link |38 the spring |42 rotates latch memberI 40 counterclockwise to disengage from latch member |43. The gates arethen under full control of the ilyballs 48. The amount of gate vaneopening permitted by the above described latching device is determinedby the adjustment of the length of link |46. Thus when the effectiveportion of the link is shortened, the degree of opening of gate vanes isdecreased while increase of the effective length of the link |46increases the amount of gate vane opening permitted.

If for any reason, such as need for repairing of the automatic controlportions of the governor system, it is necessary that such automaticportions be put out of operation; the prime mover generating unit may becontinued in operation under manual control. Such control includes amanually operated valve |5`| receiving pressure from the pipe 32 througha valve |52 and allowing flow of pressure to the opening and closingsides respectively of the gate operating servomotor I2, I3 by way ofvalves |53 and |54.

Pressure is discharged `from the manual pilot valve back to the oilpressure source by wayof a pipe |56. The valves |52, |53 and |54 areshown as being of the rotary type andas having their severalstemsinterconnected by common operating means |51 which is actuated by asingle hand wheel |58. The valves |52;A |53 andv lill are shown ascontrolling the flow of pressure to both the automatic pilot valve i4andthe manual pilot valve |5| from a single set of pipes but it will beunderstood that other arrangements or pipes and valves may be used solong as means are provided for simultaneously changing all connectionsfrom automatic pilot-I valve hito manual pilot valve |`5|.` y manuallyoperated pilot valve |5| has pivotally connected therewith a lever |354,`the ends of which are connected by way of ylinks |62 and |63 with onearm each of bell cranks'i'll andv control the iiow of fluid `pressurevto the gate' servomotor I2, i3, but all movements of the gateservomotor are relayed back to the valve I5! returning the valve to theneutral position after each movement thereof and the valve cannot beopened beyond theposition-'determined by the setting of the load limitmeans.

Hydraulic turbines in which the runner varies are adjustable can operateat-'their maximum efciency only if a predetermined relation ismaintained between the runner` vane setting and the gate vane openingand such relation must be variable for different heads under which'theturbine is to operate. The runner vanes are operated or adjusted `bytheservomotor |53, 2B

responsive to fluid pressure controlled by the pilot valve 2d. Operationof the gate servomotor l2, i3 causes movement of the relay cable 5|which rotates pulley 55 mounted on a xed portion of the governor base.rllhe rotation of the pulley acts through rod |1| on an arm |12 keyed ona shaft on which is secured a holder |13 for a plurality of cams I'lflhaving diierent cam sur-v faces formed to give the proper runner vanesetting-gate opening relation'for different heads. A cam follower ridesonythe rsurfacev of one of the cams |113 and transmits cam `movement toa shaft |11.I

Movement of the shaft y|11 is vtransmitted to a lever |82 mounted on theshaft and connected through a compression spring connection |89 |84rotatable on the shaft and with a cam grooved in one end to provideaseat for a cable 85 which is used to allow placing ofthe governingsystem at a considerable distance from the prime mover itself. 'vl-hecable |85 extends from the cam |84 to a similar cam lmounted on a pivot|81 which is on or closely adjacent pilot.

valve 2B which is itself mounted on or adjacent the primemover-generating unit; An'arm |88 is connected with cam |86 and isconnected by way of a link |89 with a floating lever lili to which isconnected the stem 29 of the pilot valve 28. connected by-Way of Valinkr|92 witha cross head |93 guided in vertical movementy by the walls Thestem |59 of the' The other end of the floating lever |9| isl of the oildistributing head 26, 21V and connected to apr'od |94 mounted onthe tube23 and therefore movable with vsuch tube. A dashpot 2| 3 with anadjustable valve 2|4 is mountedadjacent the camy |81! and is connectedtherewith to obtain smooth and regular movement of the linkage requiredfor movement of the valve 28. The

.rate of movement of the dashpot is controlled by adjustment of theVvalve lflfor controlling the by-passing of fluid around the piston ofthe dashpot. The dashpot regulates the speed of movement of the runnervarie control means whichl vary the action of thegate operating meansand the spring |83 allows overtravel of the runner control means in thedirection of adjustment of thevanes tov steep position. l y

WhenL an adjustable vanev propeller turbine-is shut down, the gatesy areclosed. and the runner vanes are turned to nat position.l In suchatposition of the runner varies, the runner vanes can, however, produceonly' a very small torque and it is desirable to set vthe runner variesinitially in steep position and to return the runnervanes to the'control of the propercam` only after/the turbine has commenced rotating.A power cylinder |96 -ismountedadjacent the cams-'|14` and is provided'with a piston |91 under the compres-` .sion of a spring |98. Fluidpressure may beV admitted to the cylinder |96 from the pipe 3| throughvalve |99 and may discharge from the cylinder through valve 209. -Thetwo valves |99 and 200 are under spring pressure' and areinterconnected. to be operatedv bythe same lever 2122- actuated by asolenoid 2|.'I3Y which maybe ener-1 gized either automatically orA underVmanual control durng starting of theturbine or when-'the turbine is tobe started. Upon opening of the valve |99 uid pressure liftsthe piston|91fand the piston rod rises into contactv with a lever 201| which'i'skeyed tothe shaft |11 and is capable ofv rotating the shaft to liftthefollower |16 off cams yI'lll and to cause movement of thelinkagenecessary to operate the `pilot 28m a direction toadmit pressureto the upper side of `the runner. servomotor I9, 20 for moving therunner varies into steepposition. Upwardmovement of piston |91 1's`limited by a stop-|95 threaded into 'cylinder |96 and having the Iod ofIpiston-|311 passing therethrough. `After the turbine hasV commencedrotating, solenoid 293 is deene'r'gizedand valves |99 'and 200'areclosedand openedfrespectively to allow discharge of pressure fro'm'the-cyl-vinder |96. The spring"^|96 then returns thepiston |91`to the endof thecylinder and the entire cam follower mechanism connected with lever 264returns to the initial position thus bringing cam follower |16again-tothesurface'of the cams |14 which then take over the control ofthe pilot valve 28 in a predetermined relation tothe moveN ment of thegate operatingmeans. `l

If some emergency requires that the oil pressure necessary for operatingthe entire governing system be conserved, it is essential rthat therunner vane movement be temporarily interrupted. `Mechanical'lockingmeans are therefore provided for preventing operation of the valve 28 solongas the -oilpressure is below ai predetermined value. A- gear'sector286" is keyed on the shaft |11 and engages a gear 291 mounted on orformed A piuraiity'of as portion of a brake'drum 2|l'8. brake shoes`2||9`are pivotedfor movement' into and out of vcontact with thedrum-208and are inwith the vcoreA of solenoid -2A E1iergization'V ofv thesolenoid 2|| is preferably controlled respon--V terconnected by a.linkagefZ 0 vwhich is connected sive to oil pressure so as to energizethe solenoid when the oil pressure drops below a predetermined value.The brake shoes 209 are then drawn against the brake drum 208 and thevalve 28 is held in xed position until the oil pressure rises and againcauses deenergization of the solenoid 2| I.

For purposes of simplicity of illustration and description, thesynchronizing screw 39 and the load limit screw 89 have been shown inFig. 1 as being locally and manually operated whereas it is desirablethat each of such screws be provided with remotely controllablereversible power operating means in place of reversible hand wheels 4|and 9|. ASuch means are shown in Fig. 2 as electric motors 2|6fand 2I1,respectively. When such electric motors are used, it is necessarytoprovide means which will prevent overtravel of the synchronizing screw39 in the gate opening direction after the gate has reached itspredetermined maximum load position. An arm 2|8 ls xed on shaft 83 andcarries a switch 2I9 which is shown as being of the tilting mercurytype, for controlling-the opening and closing of an electric circuit 220of the motor 2 I 6, the switch being responsive to the movement of theshaft 83. The switch 2I9 is so placed that circuit 220 is interruptedwhen the load limit finger 82 contacts with collar 8| and the motor 2|6cannot then be further energized.

Overtravel in gate closing direction of the load limit screw operatingmotor 2|1 is prevented by interruption of the circuit 223 thereof uponoperation of a switch 224 which is mounted on an arm 225 pivoted on thegovernor base 96. The arm 5 225 is connected through a spring 226 withan arm 221 xed on the shaft |29 which is rotatable upon energization ofthe solenoid |26. The arm 225 is also pivotally connected with a tube229 within which slides a rod 230 pivotally mounted on a crank 23|rotatable about a fixed point 232 and having a slot engaging a pin 233projecting from the traveling nut 88 of the load limit adjusting means.When the crank 23| is in the position at'which the turbine gate isclosed, the end ofthe rod 230 abuts on a pin inserted in one of thepairs of holes 234 in the tube 229, and the switch 224 cannot be closed.Energization of the solenoid |26 which pulls up on the arm 221 thenmerely stretches spring 226 because movement of the arm 225 is blocked`by abutment of the rod 230 on the pin in the tube 229.

The sequence of operationof the governing system will now be brieflydescribed from the normal shut down position shown in Fig. 1 of thedrawings through the starting operation, power limiting action, partialshut down to no load synchronous speed and complete shut down of theunit. Starting of the system involves only rotation of the synchronizingscrew 39 to raise the gate pilot valve I4 and energization of the solenoid 203 to cause the piston |91 to raise the runner pilot valve 28.Gate 9 is then opened until the relayed movement of servometer I2, I3acts through rod 92 to cause latch member |43 to engage latch member |40which rotates finger 82 clockwise into contact with collar 6I.V Thedegree of opening of gate 9 is thus limited by the setting of latch |40,|43. Raising of the runner pilot valve 28 admits pressure on top of therunner servomotor piston I9 to place the runner vanes I1 in steepposition for starting. Adjustment of the synchronizing screw 39 iscontinued until flyballs 48 are extended at approximately synchronousspeed ofthe unit when the bracket` |36 is lifted by the fiyballservomotor 44 to allow movement of the latch member |40 whereupon latch|40, |43 is disengaged by the action or springs |42 and |44. Solenoid203 is then deenergized and cam follower |16 comes to rest on apredetermined cam surface |14 to allow the runner pilot valve 28 todischarge suicient pressure to bring the runner varies I1 back to theposition determined by the contour of cam |14 then under the camfollower |16. The power limiting screw 89 is then rotated to placefinger 82 in such relation to collar 8| as is desired to limit the poweroutput of the unit to a predetermined value. The unit is now in fulloperation under the control of the ilyballs and will deliver power up tothe maximum limit set and at only such speed variations as are permittedby adjustment of the speed droop control modifying the connections forrestoring the gate pilot valve I4 to its mid position.

Upon the occurrence of a temporary and not dangerous abnormal operatingcondition, solenoids |96 and |08 are energized to allow discharge ofpressure from the power cylinder 91, 98. Spring 99 forces piston 93 downand raises crank III into contact with link IIS. Downward movement ofpiston 98 continues until the piston rod engages crank II'| whichprevents the piston from moving to the extreme end of the cylinder.Shaft 83 is rotated to bring ringer 82 down on collar 8| to cause gatepilot valve I4 to discharge sufficient pressure from the gate servomotorl2, I3 to close the gate to the extent at which the unit will operate atsynchronous speed under no load only. If an abnormal condition occurswhich is dangerous to continued operation of the unit, solenoid |26 isenergized and raises push rod |32 to force roller I I9 off surface |22to trip crank III which then allows spring 99 to push piston 98 to theend of cylinder 91 and raises crank III further to force finger 82 downon collar 8| with sufcient pressure to move the gate pilot valve I4 tothe position at which full uid pressure is admitted to the right handside of the gate servomotor I2, I3 to close gate 9 completely. Suchcomplete closing of gate 9 of course also so adjusts runner pilot valve28 as to place the runner vanes I1 in ilat position. The machine is thencompletely shut down and solenoicls |08 and |26 must be deenergized and|08 energized to again place `the shut down device in the position shownbefore the system can be restarted.

It is believed that the operation of the several locks for the runnervanes, of the interlocks for the power limit and synchronizing screwsand of the manually operable valve, have been so clearly described thatfurther description is not required of the separate operations of suchmeans which do not enter the ordinary sequence of operations of thegoverning system.

It will therefore be understood that the present invention providesnormally operating means including a pilot valve I4 and the servomotorI2, I3 for operating the gate 9. Such gate operating means is controlledby speed responsive means including motor 49, yballs 48, servomotor 44and leverage 43, 42 and 38. The gate pilot valve I4 and the servomotorI2, I3 are returned to mid position by the cable 5| acting throughpulley 54 on the dashpot 58-5I and through leverage 66, 61 on theleverage 43, 42 and 39. Such restoring action is modied by the leverage1I, 12, 14 and 16 topermit a predetermined f speed droop. The means forlimiting the degree of gate opening during starting 'includes thebracketV |36 acting on the leverage |31, |39, lthe latch MD and thefinger 82 cooperating with the rod 82, crank |41 and latch |43actuatedfrom the restoring means. Finger S2 also acts'a's a portion of themaximum power output limiting means which includes the rod 92,-crank 81,link 8S and arm 84. The runner vane control mechanism includes normallyoperating means which are required for steep tilting of the runner vanesduring starting and which-comprises valves |99 and 253%, power cylinder96, |91 and-lever 264 acting on the mechanism for maintaining apredetermined relation between gate position and runner vane positionduring normal"runningA of the unit. Such runner vane control mecha-inisrnv includes a plurality of cams l1@ and cam follower |16 actingthrough an over-travel spring |33, under the modifying action of adashpot |98, on the runner pilot Valve 28 connected to the leverage Hi8-ld for actuating the valve 28 and for restoring such valve to midposition after each movement of the runner servomotor piston I9.

The system also includes a plurality of means` of the crank ||1 uponactuation of the push rod |32 under control of the solenoid |26. Theautomatically operating valve Ul may be superseded by manually operablemeans including -valves |52, |53 and |55 and valve |51 which isinterconnectedr with the restoring means by way of rod |61 and with thepower vlimit means by Way of rod |68. The position of the runner vanesl1 is iixed on the occurrence of abnormal conditions by the brake 2F38to 2H' inclusive and by valves 2&1 and 268 acting on the power cylinder244', 2&5 to actuatethe valves 24| and 242 which lock the runner vanemechanism mechanically and hydraulically respectively. f

Although but one embodiment of the present invention has beenillustrated and described, it

will be apparent to those skilled in the art that various changes andmodications may be made therein without departing from the spirit of theinventionv or from the scopeA o the appended claims. l

It is claimed and desired to secure by Lettersl Patent:

1. In a governing system forv a prime mover having a gate controllingthe iiow of fluid thereto, a pressure operated servomotor for operatingthe gate, a pilot valve movable away from the mid-position thereof forcontrolling pressure now to said servomotor, means responsive to thespeed of the prime mover for automatically actuating said valve, meansactuated by said servomotor for restoring said valve to mid-position,and manually operable means supersedingl pilot valve in the control ofsaid servomotor.

2. In a governing system for a prime mover having a gate controlling theow of fluid thereto, a pressure operated servomotor for operating thegate, a pilot valve movable away from the mid-position thereof forcontrolling pressure flow to said servomotor, means responsive to thespeed of the prime mover for automatically actuating said valve, meansactuated by said servomotor for restoring said valve to mid-position,means for limiting Vthe `power output of the prime mover,

manually operable means for superseding said pilot valve in control ofsaid servomotor, and means connecting said manually operable means withsaid restoring means andwith said power limit means.

3. In a governing system for a prime mover having a gate controlling theflow of nuid thereto, a pilot valve controlling operation of the gate,

means responsive to the speed ofthe prime mover for moving said pilotvalve away' from the midposition thereof to cause movement of the gatemeans for restoring saidpilot valve tothe midposition thereof, meansconnecting said pilot valve with said restoring means to limit the poweroutput of the prime mover, and an adjustable leverage so associated withsaid restoring means as to limit the degree of normal speed droop of theprime mover.

4. In a governing system for a prime mover having a gatecontrolling theflow of fluid thereg pilot valve and interruptingthe circuit oftheymotor.

5. In a governing system for a prime mover havingl a gate controllingthe flow of fluid thereto and in which openingof said gate is controlledduring starting to prevent overspeeding, means responsive tov the speedof the prime mover,

means for operating said gate, a pilot valve mov-V able frommid-position for controlling movement ofsaid gate operating means, alinkage connect-fr ing said speed responsivemeans with said pilotvalve,-Ineans 4connected with said linkage lfor moving said pilot valvefrom its mid-position' during starting, restoring mechanism associatedwith said gate operatedy means/and with saidr linkage forreturning thepilot valve to mid-position, a finger adapted to be moved into and outof position coacting with a movablepart of said valve for `preventingmovement, during starting of said prime mover, of said valve'frommidposition by said means for moving said valve,

latch means controlled by saidrestoring mechanism and tending toposition said finger to prevent movement of said pilot valve, andmeansconnecting said speed responsivegmeans and said latch means andtending to move said linger lout of position for preventing movement ofsai'dipilot valve, said latch means and itsassociated means cooperatingto prevent opening of said gate until said speed responsive meansattains a speed directly proportional to the' speed of the prime moverand thereby' preventing overspeeding of said gate operating means, alinkage connect-` ing said speed responsive means with said pilot valve,means connectedv with said linkage for moving said pilot valve from itsmid-position during starting, restoring mechanism associated with saidgate operated means and with said linkage for returning the pilot valveto mid-position, a finger adapted to be moved into and out of positioncoacting with a movable part of said valve for preventing movement,during starting of said prime mover, of said valve from mid-position bysaid means for moving said valve, latch means controlled by saidrestoring mechanism and tending to position said finger to preventmovement of said pilot valve, means connecting said speed responsivemeans and said latch means and tending to move said finger out ofposition for preventing movement of said pilot valve, said latch meansand its associated meansv `cooperating to prevent opening of said gateuntil said speed responsive means attains a speed directly proportionalto the speed of the prime mover and thereby preventing overspeedingthereof, and means for adjusting said latch means to determine theposition at which said finger becomes effective for preventingrmovernentof said pilot valve from mid-position. y

'7. In a governing system for a prime mover having a gate controllingthe ow of iiuid thereto and in which opening of said gate is controlledduring starting to prevent overspeeding, means responsive to the speedof the prime mover, means for operating said gate, a pilot valve movablefrom mid-position for controlling movement of said gate operating means,a linkage connecting said speed responsive means with said pilot valve,means connected with said linkage for moving said pilot valve from itsmid-position during starting, restoring mechanism associated with saidgate operated means and with said linkage for returning the pilot valveto mid-position, a finger adapted to be moved into and out oi positioncoacting with a movable part ci said valve for preventing movement,during starting oi' said prime mover, of said valve from midposition bysaid means for moving said valve, latch means controlled by saidrestoring mechanism and tending to position said ringer to preventmovement of said pilot valve, said latch means comprising a plurality ofenacting members, one of said members being actuated by said speedresponsive means and the other of said members being actuated by saidrestoring mechanism, and means connecting said speed responsive meansand said latch means and tending to move said finger out of position forpreventing movement of said pilot valve, said latch means and itsassociated means cooperating to prevent opening of said gate until'saidspeed responsive means attains a speed directly proportional to thespeed of the prime mover and vthereby preventing overspeeding thereof.

`8. In a governing system for a prime mover having a gate controllingthe ilow of fiuid thereto and in which opening of said gate iscontrolled during starting to prevent overspeeding, means responsive tothe speed of the prime mover, means for operating said gate, a pilotvalve movable from rmid-position for controlling movement of said gateoperating means, a linkage connecting said speed responsive means withsaid pilot valve, means connected with said linkage for moving saidpilot valve from its mid-position during starting, restoring mechanismassociated with said gate operating means and with said linkage forreturning the pilot valve to midposition, a nger adapted to be movedinto and out of position coacting with a movable part of said valve forpreventing movement, during starting of said prime mover, of said valvefrom midposition by said means for moving said valve, latch meanscontrolled by said restoring mechanism and tending to position saidfinger to prevent movement of said pilot valve, said latch meanscomprising a plurality of coacting members, one of said members beingactuated by said speed responsive means and the other of said membersbeing actuated by said restoring mechanism, means connecting said speedresponsive means and said lat/ch means and tending to move said nger outof position for preventing movement of said pilot valve, said latchmeans and its associated means cooperating to prevent opening of saidgate until said speed responsive means attains a speed directlyproportional to the speed of the prime mover and thereby preventingoverspeeding thereof, and means for severally adjusting the initialpositions of said latch members.

9. In a governing system for a prime mover having a gate controlling theflow of iluid thereto, a pilot valve controlling operation of the gate,means responsive to a departure of the prime mover from normal speed formoving said pilot valve away from the mid-position thereof and causingmovement of the gate, means responsive to gate movement for restoringsaid pilot valve to the mid-position thereof, means associated with saidpilot valve and with said restoring means to limit the power output ofthe prime mover, motor operated means for adjusting the setting of saidpower limiting means to adjust the load limit of the prime mover, acircuit for said motor including a switch, said switch being soassociated with said power limit means as to be capable of being closedwhen said power limit means has a setting corresponding to gate openpositions and as to be incapable of being moved into closed positionwhen said power limit means is in gate closed position.

JOSEPH J. RING. BEVERLY R. NICHOLS.

